Just inside the front cover, they posed the question, "How many days would you like to ride?" On a map of the USA, with a number for each of the major cities. The "fine print" says it's the average number of days when the temperature is above 25, and below 95.
Boise's number is 284.
For comparison purposes... Seattle's is 356. Portland - 358, Salt Lake City 229, Spokane 291, Denver 269. San Diego is 364! Honolulu - the champ at 365.